Hydatid Disease in Australia. 



By J. Daties Thomas, M.D., London. 



[Eead October 3, and November 7, 1882.J 



[abeidged.] 



The Eg jal Society has on several occasions shown an interest 

 in questions respecting the common weal and health, and has, 

 I feel sure, contributed to no small degree in educating the 

 public on some matters closely connected wdth general hygiene. 

 I therefore venture to think that any communication which has 

 for its object the prevention of disease, pain, and death will 

 meet with lenient criticism and friendly reception from the 

 members of this Society. 



Apart from the importance of the hydatid as a cause of 

 disease in man and stock, its study is of great interest from a 

 purely scientific point of view ; so that any hesitancy I may 

 feel is not because the subject is bald of interest, but rather 

 lest the writer may prove unequal to his theme. 



In dealing with hydatids, there are two points of view from 

 which the subject may be regarded. Thus we may consider it 

 merely from a biological standpoint, and study the parasite 

 itself, its mode of origin, growth, and death, in the various 

 phases of its life-history ; or we may consider it from a medical 

 aspect, as causing a disease often great in its painfulness and 

 terrible in its danger to man and beast. 



In connection with this latter view we might further discuss 

 (1) the mode of its prevention, and (2) the best mode of treat- 

 ment when it is present. The subject will, however, be pre- 

 sented to your notice only as a brief summary of what I have 

 been able to learn about the prevalence of hydatid disease in 

 man, and chieily as concerns the Southern Hemisphere; and I 

 shall also endeavour to point out how therrisk of infection may 

 be reduced to more moderate limits. On our way we shall 

 see that there are many points upon which more information is 

 needed, and in the investigation of which some members of 

 this Society may do good service to science and to public 

 health. 



Dr. Thomas then gave an exhaustive account of the natural 

 history of Echinococcus, as far as present knowledge of the 



